No abstract

The available data indicate that EVT is feasible, safe and effective with good short-term and long-term clinical outcomes in the damage control of upper GI-tract leaks. Still, a prospective multi-center study has to be conducted to proof the definite benefit of EVT for patients with esophageal defects.

BackgroundColorectal cancer (CRC) represents a morphologic and molecular heterogenic disease. This heterogeneity substantially impairs drug effectiveness and prognosis. The subtype of mismatch repair deficient (MMR-D) CRCs, accounting for about 15% of all cases, shows particular differential responses up to resistance towards currently approved cytostatic drugs. Pre-clinical in vitro models representing molecular features of MMR-D tumors are thus mandatory for identifying biomarkers that finally help to predict responses towards new cytostatic drugs. Here, we describe the successful establishment and characterization of three patient-derived MMR-D cell lines (HROC24, HROC87, and HROC113) along with their corresponding xenografts.MethodologyMMR-D cell lines (HROC24, HROC87, and HROC113) were established from a total of ten clinicopathological well-defined MMR-D cases (120 CRC cases in total). Cells were comprehensively characterized by phenotype, morphology, growth kinetics, invasiveness, and molecular profile. Additionally, response to clinically relevant chemotherapeutics was examined in vitro and in vivo.Principal FindingsTwo MMR-D lines showing CIMP-H derived from sporadic CRC (HROC24: K-raswt, B-rafmut, HROC87: K-raswt, B-rafmut), whereas the HROC113 cell line (K-rasmut, B-rafwt) was HNPCC-associated. A diploid DNA-status could be verified by flow cytometry and SNP Array analysis. All cell lines were characterized as epithelial (EpCAM+) tumor cells, showing surface tumor marker expression (CEACAM+). MHC-class II was inducible by Interferon-γ stimulation. Growth kinetics as well as invasive potential was quite heterogeneous between individual lines. Besides, MMR-D cell lines exhibited distinct responsiveness towards chemotherapeutics, even when comparing in vitro and in vivo sensitivity.ConclusionsThese newly established and well-characterized, low-passage MMR-D cell lines provide a useful tool for future investigations on the biological characteristics of MMR-D CRCs, both of sporadic and hereditary origin. Additionally, matched patient-derived immune cells allow for comparative genetic studies.

EVT is a promising approach for postoperative, iatrogenic, or spontaneous lesions of the upper GI tract. In this series, EVT was combined with operative revision in a relevant proportion of patients.

To our knowledge, this retrospective observation of EVT application for rectal lesions represents the largest patient series in literature. EVT has earned its indication in complication management after colorectal surgery and can achieve a successful control of a local septic focus in the majority of patients.

Conclusion: These results suggest a functional role of HERV-H sequences in colorectal carcinogenesis. The pronounced connection with microsatellite instability warrants a more detailed investigation. Thus, HERV-H sequences in addition to tumor specific mutations may represent clinically relevant, truly CRC specific markers for diagnostic, prognostic and therapeutic purposes.

Background Anastomotic leakage after rectal resection represents a severe complication for the patient and requires an early and appropriate management. Endoscopic vacuum therapy (EVT) has become the treatment of choice for anastomotic leakage after rectal resection in several institutions in Germany, and commercially available systems are currently distributed in approximately 30 countries worldwide. However, there is no evidence that EVT is superior to any other treatment for anastomotic leakage after rectal resection. Methods Twenty-one patients treated with EVT for anastomotic leakage after rectal resection were retrospectively compared to a historical cohort of 41 patients that received conventional treatment. Primary endpoints were death, treatment success and long-term preservation of intestinal continuity. Secondary endpoints were length of hospital stay and duration of treatment.Results There was no difference in mortality (p = 0.624). The intention-to-treat analysis showed a significantly higher success rate of EVT compared to conventional treatment (95.2% vs. 65.9%, p = 0.011). EVT was associated with preservation of intestinal continuity in a significant higher percentage of patients than patients undergoing conventional treatment (86.7% vs. 37.5%, p = 0.001). Conventional treatment tended to a shorter length of hospital stay (31.1 vs. 42.2 days, p = 0.066) but with no difference in overall duration of treatment. Time until closing of a diverting stoma did not differ between groups (10.2 months in the EVT group vs. 9.4 months in the conventional treatment group, p = 0.721). Conclusion According to this retrospective study, conventional therapy and EVT are both options for the treatment of anastomotic leakage after rectal resection. EVT might be more effective in terms of definite healing and preservation of intestinal continuity.

We successfully established and characterized novel ultra-low passage patient-derived CRC models as useful instruments for analyzing biological characteristics associated with the CIN(+) phenotype.